1. Field of the Invention
The present invention relates to a display control method for display devices that display an image obtained by perspective-projecting an image model located in a virtual three-dimensional coordinate space onto a two-dimensional plane in the prescribed view line direction. More particularly, the present invention relates to an image display control method making it possible to control the displayed image following the displacement of the view line direction or the movement of the view point position by the player's operations in a shooting game.
2. Description of the Related Art
There are shooting games in which an image obtained by perspective-projecting a three-dimensional spatial image model comprising a character image, which is a target, in a virtual three-dimensional coordinate space onto a two-dimensional plane in the view line direction is displayed on a display device and the game is advanced by simulation shooting at the displayed character image with a simulation gun operated by a player.
As an example of such a shooting game, a technology was suggested (Japanese Patent Application Laid-open No. 2002-18128) in which the simulation gun (gun-type controller) was provided with an input key such as a cross-direction key and the selection operations such as the movement of the character operated by the player, changes in the disposition of the enemy character, and weapon used by the characters were facilitated.
On the other hand, it is expected that in the shooting game a feeling of virtual reality shooting be created for the player by changing the view line direction or view point position in the virtual three-dimensional coordinate space according to the intensions of the player himself so as to confront the enemy character.
However, in the conventional shooting games, the displayed images change according to the preset program and the player can change the observation point of the gun-type controller only within a range of prescribed displayed images that are displayed according to the program. Thus, the view line direction or view point position in the virtual three-dimensional coordinate space are not changed by the player's operations.
Therefore, the view line direction and view point position are fixed unless the displayed image on the screen is changed by the program, and the range for taking aim with the gun-type controller is fixed in advance by the program. Thus, the idea of timely changing the view line direction or view point position by the player's operations and changing the range for taking aim with the gun-type controller did not exist as prior art technology.
The aforementioned Japanese Patent Application Laid-open No. 2002-18128, too, contained no description suggesting the technology of changing the view line direction or view point position by the player's operations.